I'm getting married in 3 weeks... Any advice?

I'm really not concerned about the marriage part... My partner is great and we have a great relationship

But the wedding part has me stressing. I'm not a decorator at all but I'm in charge of the decorations. I'm pretty much in charge of everything except the food (my dad is taking care of the food). It's a bit overwhelming and I don't want my wedding to be tacky or sucky but I have zero concept of what is tacky or what a wedding should be like.